Signal processing method

ABSTRACT

A signal processing method is provided. The signal processing method is used in a Gigabit Ethernet system including a device under test (DUT) and a link partner (LP), and includes the following steps. Firstly, an interference detector is configured to detect whether the Gigabit Ethernet system is interfered by other signal sources. Next, a physical layer (PHY) of the DUT or a PHY of the LP is used to, in response to the Gigabit Ethernet system being interfered by the other signal sources, set a request signal indicating whether or not the physical layer enters a low power idle (LPI) mode as FALSE. Which PHY of the DUT and the LP is used to set the request signal indicating whether or not the PHY enters the LPI mode as FALSE depends upon which one of the DUT and the LP is provided with the interference detector.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application claims the benefit of priority to Taiwan PatentApplication No. 109122176, filed on Jul. 1, 2020. The entire content ofthe above identified application is incorporated herein by reference.

Some references, which may include patents, patent applications andvarious publications, may be cited and discussed in the description ofthis disclosure. The citation and/or discussion of such references isprovided merely to clarify the description of the present disclosure andis not an admission that any such reference is “prior art” to thedisclosure described herein. All references cited and discussed in thisspecification are incorporated herein by reference in their entiretiesand to the same extent as if each reference was individuallyincorporated by reference.

FIELD OF THE DISCLOSURE

The present disclosure relates to a signal processing method, and moreparticularly to a signal processing method that can prevent a GigabitEthernet system from entering and exiting a low power idle (LPI) modeunder interference from other signal sources and resulting in connectionfailure.

BACKGROUND OF THE DISCLOSURE

In order to reduce power loss of integrated circuits and achieveenergy-saving purposes, IEEE 802.3 standards have formulated a low poweridle (LPI) mode. In the LPI mode, a device under test (DUT) and a linkpartner (LP) of a Gigabit Ethernet system will stop transmitting dataand stop operations of most circuit components, thereby achieving powersaving effects. For example, references are made to FIGS. 1A and 1B.FIGS. 1A and 1B are control state diagrams of a physical layer (PHY)defined by the IEEE 802.3 standards. As shown in FIG. 1A, after enteringSEND IDLE OR DATA state, in order for the PHY of the DUT or the PHY ofthe LP to enter the LPI mode, the following five conditions must be met:

minwait_timer_done;

loc_rcvr_status=OK;

rem_rcvr_status=OK;

loc_lpi_req=TRUE; and

rem_lpi_req=TRUE.

It should be noted that loc_lpi_req is a request signal indicatingwhether or not a PHY of a local end enters the LPI mode, and rem_lpi_reqis a request signal indicating whether or not a PHY of a remote endenters the LPI mode. In other words, the PHY of the local end can setloc_lpi_req as TRUE or FALSE according to whether the PHY of the localend enters the LPI mode, and the PHY of the local end will receiveloc_lpi_req from the PHY of the remote end as rem_lpi_req. It can beseen that the LPI mode of the Gigabit Ethernet system is bidirectionaland symmetrical. Therefore, if one of the PHY of the DUT and the PHY ofthe LP does not send the request signal for entering the LPI mode, thePHY of the DUT and the PHY of the LP must continue to be in the SENDIDLE OR DATA state to send data or idle signals.

In addition, in the LPI mode, since the operations of most of thecircuit components have stopped, resistance of the Gigabit Ethernetsystem to environmental changes will be greatly reduced, especially ifthere is interference from other signal sources in the environment. Oncethe Gigabit Ethernet system exits the LPI mode, the Gigabit Ethernetsystem must properly adjust the state within a specified time, orfilters thereof must be properly converged in a very short time.Otherwise, the Gigabit Ethernet system will risk losing packets, or evenmore seriously, connection failure (Link Down). Therefore, providing amethod to prevent the Gigabit Ethernet system from entering and exitingthe LPI mode under interference of other signal sources, which mayresult in connection failures, has become an important issue in therelated art.

SUMMARY OF THE DISCLOSURE

In response to the above-referenced technical inadequacies, the presentdisclosure provides a signal processing method, which is used in aGigabit Ethernet system including a device under test (DUT) and a linkpartner (LP).

The signal processing method includes the following steps. Firstly, aninterference detector is configured to detect whether the GigabitEthernet system is interfered by other signal sources. Next, a physicallayer of the DUT or a physical layer of the LP is used to, in responseto the interference detector determining that the Gigabit Ethernetsystem is interfered by the other signal sources, set a request signalindicating whether or not the PHY enters a low power idle (LPI) mode asFALSE. Further, which one of the physical layer of the DUT and thephysical layer of the LP is used to set the request signal indicatingwhether or not the physical layer enters the LPI mode as FALSE dependsupon which one of the DUT and the LP the interference detector isprovided on.

These and other aspects of the present disclosure will become apparentfrom the following description of the embodiment taken in conjunctionwith the following drawings and their captions, although variations andmodifications therein may be affected without departing from the spiritand scope of the novel concepts of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure will become more fully understood from thefollowing detailed description and accompanying drawings.

FIGS. 1A and 1B are control state diagrams of a physical layer (PHY)defined by IEEE 802.3 standards.

FIG. 2 is a flow chart of a signal processing method provided by anembodiment of the present disclosure.

FIG. 3 is a schematic diagram showing the signal processing method ofFIG. 2 used for a PHY of a link partner (LP) to exit from a low poweridle (LPI) mode in an UPDATE state, such that both a PHY of a deviceunder test (DUT) and the PHY of the LP exit from the LPI mode.

FIG. 4 is a schematic diagram showing the signal processing method ofFIG. 2 used for the PHY of the LP to exit from the LPI mode in aPOST_UPDATE state, such that both the PHY of the DUT and the PHY of theLP exit from the LPI mode.

FIG. 5 is a schematic diagram showing the signal processing method ofFIG. 2 used for the PHY of the LP to exit from the LPI mode in aWAIT_QUIET state, such that both the PHY of the DUT and the PHY of theLP exit from the LPI mode.

FIG. 6 is a schematic diagram showing the signal processing method ofFIG. 2 used for the PHY of the DUT to exit from the LPI mode in theUPDATE state, such that both the PHY of the DUT and the PHY of the LPexit from the LPI mode.

FIG. 7 is a schematic diagram showing the signal processing method ofFIG. 2 used for the PHY of the DUT to exit from the LPI mode in thePOST_UPDATE state, such that both the PHY of the DUT and the PHY of theLP exit from the LPI mode.

FIG. 8 is a Local LPI Request state diagram modified according to thesignal processing method of FIG. 2.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

The present disclosure is more particularly described in the followingexamples that are intended as illustrative only since numerousmodifications and variations therein will be apparent to those skilledin the art. Like numbers in the drawings indicate like componentsthroughout the views. As used in the description herein and throughoutthe claims that follow, unless the context clearly dictates otherwise,the meaning of “a”, “an”, and “the” includes plural reference, and themeaning of “in” includes “in” and “on”. Titles or subtitles can be usedherein for the convenience of a reader, which shall have no influence onthe scope of the present disclosure.

The terms used herein generally have their ordinary meanings in the art.In the case of conflict, the present document, including any definitionsgiven herein, will prevail. The same thing can be expressed in more thanone way. Alternative language and synonyms can be used for any term(s)discussed herein, and no special significance is to be placed uponwhether a term is elaborated or discussed herein. A recital of one ormore synonyms does not exclude the use of other synonyms. The use ofexamples anywhere in this specification including examples of any termsis illustrative only, and in no way limits the scope and meaning of thepresent disclosure or of any exemplified term. Likewise, the presentdisclosure is not limited to various embodiments given herein. Numberingterms such as “first”, “second” or “third” can be used to describevarious components, signals or the like, which are for distinguishingone component/signal from another one only, and are not intended to, norshould be construed to impose any substantive limitations on thecomponents, signals or the like.

Reference is made to FIG. 2, which is a flow chart of a signalprocessing method provided by an embodiment of the present disclosure.It should be noted that the signal processing method of FIG. 2 can beused in a Gigabit Ethernet system including a device under test (DUT)and a link partner (LP). However, the present disclosure does not limitthe specific implementation of the DUT and the LP, and those skilled inthe art can design based on actual needs or applications. As shown inFIG. 2, in step S210, the present embodiment uses an interferencedetector to detect whether the Gigabit Ethernet system is interfered byother signal sources. If the interference detector detects that theGigabit Ethernet system is interfered by other signal sources, themethod in the present embodiment proceeds to step S220; if theinterference detector does not detect that the Gigabit Ethernet systemis interfered by other signal sources, the method in the presentembodiment returns to step S210. In other words, once the interferencedetector detects that the Gigabit Ethernet system is interfered by theother signal sources, the method in the present embodiment executes stepS220.

In step S220, a physical layer of the DUT or a physical layer of the LPis used to set a request signal indicating whether or not the PHY entersa low power idle (LPI) mode as FALSE, that is, loc_lpi_req=FALSE, suchthat both the PHY of the DUT and the PHY of the LP exit from the LPImode. It is worth mentioning that the above interference detector can beimplemented in an analog circuit or a digital circuit. In short, thepresent disclosure does not limit the specific implementation of theinterference detector. In addition, when the request signal indicatingwhether or not the PHY enters a low power idle (LPI) mode is set asFALSE, which one of the physical layer of the DUT and the physical layerof the LP requests to exit from the LPI mode depends upon which one ofthe DUT and the LP is provided with the interference detector. The PHYis an electronic circuit required to implement functions of a physicallayer of an OSI model in a network interface controller, and the PHY isusually implemented as an integrated circuit.

In addition, when the PHY of the DUT and the PHY of the LP are both in aSEND IDLE OR DATA state, filters of the Gigabit Ethernet system can relyon the signal from another party to maintain synchronization andconnection status, such that resistance to interference can be greatlyimproved. Therefore, once the interference detector detects that theGigabit Ethernet system is not interfered by the other signal sources,an original setting for the PHY in the present embodiment can berestored, that is, an initiative for entering the LPI mode is returnedto be determined according to whether there is any packet to betransmitted in an upper layer.

Furthermore, as shown in FIG. 1B, the LPI mode includes an UPDATE state,a POST_UPDATE state, a WAIT_QUIET state, a QUIET state, a WAKE state,and the like. Before entering the QUIET state of the LPI mode, if thePHY of the DUT or the PHY of the LP needs to exit from the LPI mode,only the following five situations will occur:

the PHY of the LP exits from the LPI mode in the UPDATE state;

the PHY of the LP exits from the LPI mode in the POST_UPDATE state;

the PHY of the LP exits from the LPI mode in the WAIT_QUIET state;

the PHY of the DUT exits from the LPI mode in the UPDATE state; and

the PHY of the DUT exits from the LPI mode in the POST_UPDATE state.

Therefore, reference is now made to FIGS. 3 to 7. FIGS. 3 to 7 areschematic diagrams showing the signal processing method of FIG. 2 beingused in the above five situations, such that both the PHY of the DUT andthe PHY of the LP exit from the LPI mode.

As shown in FIG. 3, when the LP is provided with the interferencedetector and the interference detector detects that the Gigabit Ethernetsystem is interfered by the other signal sources when the PHY of the LPis in the UPDATE state of the LPI mode, the PHY of the LP is used to setthe request signal indicating whether or not the PHY enters the LPI modeas FALSE, and send the request signal that is set to FALSE to the PHY ofthe DUT, that is, loc_lpi_req=FALSE, and then the PHY of the LP jumpsdirectly from the UPDATE state of the LPI mode to a SEND IDLE OR DATAstate.

In contrast, when the PHY of the DUT receives the request signal that isset to FALSE by the PHY of the LP when the PHY of the DUT is in theUPDATE state of the LPI mode, the PHY of the DUT can satisfyrem_lpi_req=FALSE and rem_update_done=FALSE. Therefore, the PHY of theDUT jumps directly from the UPDATE state of the LPI mode to the SENDIDLE OR DATA state. In other words, both the PHY of the DUT and the PHYof the LP exit from the LPI mode.

Next, as shown in FIG. 4, when the LP is provided with the interferencedetector and the interference detector detects that the Gigabit Ethernetsystem is interfered by the other signal sources when the PHY of the LPis in a POST_UPDATE state of the LPI mode, the PHY of the LP is used toset the request signal indicating whether or not the PHY enters the LPImode as FALSE, and send the request signal that is set to FALSE to thePHY of the DUT. Then, the PHY of the LP waits until the PHY of the DUTenters the POST_UPDATE state of the LPI mode, i.e., the PHY of the LPsatisfying both rem_update_done=TRUE and loc_lpi_req=FALSE, beforespeeding up to enter the WAIT_QUIET state and the QUIET state of the LPImode in sequence, and then entering the WAKE state of the LPI mode.

In contrast, when the PHY of the DUT receives the request signal fromthe PHY of the LP that is set to FALSE when the PHY of DUT is in thePOST_UPDATE state of the LPI mode, the PHY of the DUT enters theWAIT_QUIET state and the QUIET state of the LPI mode in sequence untilthe PHY of the DUT receives a signal detection value set to TRUE again,that is, signal_detect=TRUE, and then the PHY of the DUT enters the WAKEstate in the LPI mode.

Next, as shown in FIG. 5, when the LP is provided with the interferencedetector and the interference detector detects that the Gigabit Ethernetsystem is interfered by the other signal sources when the PHY of the LPis in the WAIT_QUIET state of the LPI mode, the PHY of the LP is used toset the request signal indicating whether or not the PHY enters the LPImode as FALSE, that is, loc_lpi_req=FALSE, and send the request signalthat is set to FALSE to the PHY of the DUT. The PHY of the LP thenspeeds up to enter the QUIET state of the LPI mode, and then enters theWAKE state in LPI mode.

In contrast, when the PHY of the DUT receives the request signal set toFALSE by the PHY of the LP when the PHY of the DUT is in the QUIET stateof the LPI mode, until the PHY of the DUT receive the signal detectionvalue set to TRUE again, that is, signal_detect=TRUE, the PHY of DUTenters the WAKE state of LPI mode.

In addition, as shown in FIG. 6, when the DUT is provided with theinterference detector and the interference detector detects that theGigabit Ethernet system is interfered by the other signal sources whenthe physical layer of the DUT is in the UPDATE state of the LPI mode,the PHY of the DUT is used to set the request signal indicating whetheror not the PHY enters the LPI mode as FALSE, that is, loc_lpi_req=FALSE,and send the request signal that is set to FALSE to the PHY of the LP,and then the PHY of the DUT jumps directly from the UPDATE state of theLPI mode to the SEND IDLE OR DATA state of the LPI mode.

In contrast, when the PHY of the LP receives the request signal set toFALSE by the PHY of the DUT when the PHY of the LP is in the UPDATEstate or the POST_UPDATE state of the LPI mode, the PHY of LP jumpsdirectly from the UPDATE state of the LPI mode or the POST_UPDATE stateof the LPI mode to the SEND IDLE OR DATA state. The details of FIG. 6are as depicted in FIG. 3, and will not be repeated herein.

Finally, as shown in FIG. 7, when the DUT is provided with theinterference detector and the interference detector detects that theGigabit Ethernet system is interfered by the other signal sources whenthe PHY of the DUT is in the POST_UPDATE state of the LPI mode, the PHYof the DUT is used to set the request signal indicating whether or notthe physical layer enters the LPI mode as FALSE, and send the requestsignal that is set to FALSE to the PHY of the LP, and then wait untilthe PHY of the LP enters the POST_UPDATE state of the LPI mode, i.e.,the PHY of the DUT satisfying rem_update_done=TRUE andloc_lpi_req=FALSE, therefore, the PHY of the DUT speeds up to enter theWAIT_QUIET state and the QUIET state of the LPI mode in sequence, andthen enters the WAKE state of the LPI mode. It is worth mentioning thatin the embodiment of FIG. 7, since the PHY of the LP enters thePOST_UPDATE state of the LPI mode earlier than the PHY of the DUT,therefore, when the PHY of the DUT sets loc_lpi_req to FALSE when thePHY of the DUT is in the POST_UPDATE state, the PHY of the DUT hasalready satisfied rem_update_done=TRUE.

In contrast, when the PHY of the LP receives the request signal that isset to FALSE by the PHY of the DUT when the PHY of the LP is in thePOST_UPDATE state of the LPI mode or the WAIT_QUIET state of the LPImode, the PHY of the LP speeds up to enter the QUIET state of the LPImode, until the PHY of the LP receives the signal detection value set toTRUE again, that is, signal_detect=TRUE, and the PHY of the LP entersthe WAKE state of the LPI mode. The details of FIG. 7 are as describedin FIG. 4 and FIG. 5, and will not be repeated herein. In short, thepresent disclosure can modify a request state diagram of the local LPIdefined by the IEEE 802.3 standards according to the signal processingmethod of FIG. 2.

As shown in FIG. 8, compared with the existing Gigabit Ethernet system,after entering a local end LPI request to turn off (LOC LPI REQ OFF)state, when the PHY of the DUT or the PHY of the LP needs to setloc_lpi_req as TRUE, an additional condition must be met:Interference_index=FALSE. In contrast, after entering a local end LPIrequest to turn on (LOC LPI REQ ON) state, when the PHY of the DUT orthe PHY of the LP needs to set loc_lpi_req to FALSE, an additionalcondition must be met: Interference_index=TRUE. That is,Interference_index is a notification signal from the interferencedetector indicating whether or not it detects that the Gigabit Ethernetsystem is interfered by the other signal sources, andInterference_index=TRUE represents that the interference detectordetects that the Gigabit Ethernet system currently suffers interferencefrom other signal sources. Therefore, the PHY of the DUT or the PHY ofthe LP provided with the interference detector will set loc_lpi_req toFALSE, such that the PHY of the DUT and the PHY of the LP both exit fromthe LPI mode. Since other conditions of the local LPI request statediagram are already known to those skilled in the art, detailsassociated with FIG. 8 will not be repeated.

In conclusion, in the signal processing method provided by theembodiments of the present disclosure, once the interference detectordetects that the Gigabit Ethernet system is interfered by the othersignal sources, the PHY of the DUT or the PHY of the LP that is providedwith the interference detector sets loc_lpi_req as FALSE, such that thePHY of the DUT or the PHY of the LP exits from the LPI mode. That is tosay, the present disclosure can prevent the Gigabit Ethernet system fromconnection failure due to interference from other signal sources in theLPI mode by merely modifying a control flow of loc_lpi_req, and thepresent disclosure can be implemented without adding an excessive amountof hardware.

The foregoing description of the exemplary embodiments of the disclosurehas been presented only for the purposes of illustration and descriptionand is not intended to be exhaustive or to limit the disclosure to theprecise forms disclosed. Many modifications and variations are possiblein light of the above teaching.

The embodiments were chosen and described in order to explain theprinciples of the disclosure and their practical application so as toenable others skilled in the art to utilize the disclosure and variousembodiments and with various modifications as are suited to theparticular use contemplated. Alternative embodiments will becomeapparent to those skilled in the art to which the present disclosurepertains without departing from its spirit and scope.

What is claimed is:
 1. A signal processing method used in a GigabitEthernet system including a device under test (DUT) and a link partner(LP), the signal processing method comprising: configuring aninterference detector to detect whether the Gigabit Ethernet system isinterfered by other signal sources; and using a physical layer (PHY) ofthe DUT or a physical layer of the LP to, in response to theinterference detector determining that the Gigabit Ethernet system isinterfered by the other signal sources, set a request signal indicatingwhether or not the physical layer enters a low power idle (LPI) mode asFALSE.
 2. The signal processing method according to claim 1, whereinwhich one of the physical layer of the DUT and the physical layer of theLP is used to set the request signal indicating whether or not thephysical layer enters the LPI mode as FALSE depends upon which one ofthe DUT and the LP the interference detector is provided on.
 3. Thesignal processing method according to claim 1, wherein, when theinterference detector is provided on the LP and the interferencedetector detects that the Gigabit Ethernet system is interfered by theother signal sources during a time when the physical layer of the LP isin an UPDATE state of the LPI mode, the physical layer of the LP is usedto set the request signal indicating whether or not the physical layerenters the LPI mode as FALSE, and send the request signal that is set toFALSE to the physical layer of the DUT, and then the physical layer ofthe LP jumps directly from the UPDATE state of the LPI mode to a SENDIDLE OR DATA state.
 4. The signal processing method according to claim3, wherein, when the physical layer of the DUT receives the requestsignal set to FALSE from the physical layer of the LP during a time whenthe physical layer of the DUT is in the UPDATE state of the LPI mode,the physical layer of the DUT jumps directly from the UPDATE state ofthe LPI mode to the SEND IDLE OR DATA state.
 5. The signal processingmethod according to claim 1, wherein, when the LP is provided with theinterference detector and the interference detector detects that theGigabit Ethernet system is interfered by the other signal sources duringa time when the physical layer of the LP is in a POST_UPDATE state ofthe LPI mode, the physical layer of the LP is used to set the requestsignal indicating whether or not the physical layer enters the LPI modeas FALSE, and send the request signal that is set to FALSE to thephysical layer of the DUT, and then the physical layer of the LP waitsuntil the physical layer of the DUT enters the POST_UPDATE state of theLPI mode before speeding up to enter a WAIT_QUIET state and a QUIETstate of the LPI mode in sequence, and then entering a WAKE state of theLPI mode.
 6. The signal processing method according to claim 5, wherein,when the physical layer of the DUT receives the request signal set toFALSE from the physical layer of the LP during a time when the physicallayer of the DUT is in the POST_UPDATE state of the LPI mode, thephysical layer of the DUT enters the WAIT_QUIET state and the QUIETstate of the LPI mode in sequence, and the physical layer of the DUTenters the WAKE state of the LPI mode only after receiving a signaldetection value set to TRUE again.
 7. The signal processing methodaccording to claim 1, wherein, when the LP is provided with theinterference detector and the interference detector detects that theGigabit Ethernet system is interfered by the other signal sources duringa time when the physical layer of the LP is in a WAIT_QUIET state of theLPI mode, the physical layer of the LP is used to set the request signalindicating whether or not the physical layer enters the LPI mode toFALSE, and send the request signal set to FALSE to the physical layer ofthe DUT, and then the physical layer of the LP speeds up to enter aQUIET state of the LPI mode, and then enters a WAKE state of the LPImode.
 8. The signal processing method according to claim 7, wherein,when the physical layer of the DUT receives the request signal set toFALSE from the physical layer of the LP during a time when the physicallayer of the DUT is in the QUIET state of the LPI mode, the physicallayer of the DUT enters the WAKE state of the LPI mode only afterreceiving a signal detection value set to TRUE again.
 9. The signalprocessing method according to claim 1, wherein, when the DUT isprovided with the interference detector and the interference detectordetects that the Gigabit Ethernet system is interfered by the othersignal sources during a time when the physical layer of the DUT is in anUPDATE state of the LPI mode, the physical layer of the DUT is used toset the request signal indicating whether or not the physical layerenters the LPI mode as FALSE, and send the request signal that is set toFALSE to the physical layer of the LP, and then the physical layer ofthe DUT jumps directly from the UPDATE state of the LPI mode to a SENDIDLE OR DATA state of the LPI mode.
 10. The signal processing methodaccording to claim 9, wherein, when the physical layer of the LPreceives the request signal set to FALSE from the physical layer of theDUT during a time when the physical layer of the LP is in the UPDATEstate or a POST_UPDATE state of the LPI mode, the physical layer of theLP jumps directly from the UPDATE state of the LPI mode to the SEND IDLEOR DATA state.
 11. The signal processing method according to claim 1,wherein, when the DUT is provided with the interference detector and theinterference detector detects that the Gigabit Ethernet system isinterfered by the other signal sources during a time when the physicallayer of the DUT is in a POST_UPDATE state of the LPI mode, the physicallayer of the DUT is used to set the request signal indicating whether ornot the physical layer enters the LPI mode as FALSE, and send therequest signal that is set to FALSE to the physical layer of the LP, andthen the physical layer of the DUT waits until the physical layer of theLP enters the POST_UPDATE state of the LPI mode before speeding up toenter a WAIT_QUIET state and a QUIET state of the LPI mode in sequence,and then entering a WAKE state of the LPI mode.
 12. The signalprocessing method according to claim 11, wherein when the physical layerof the LP receives the request signal set to FALSE from the physicallayer of the DUT when the physical layer of the LP is in the POST_UPDATEstate or the WAIT_QUIET state of the LPI mode, the physical layer of theLP speeds up to enter the QUIET state of the LPI mode, and the physicallayer of the LP enters the WAKE state of the LPI mode only afterreceiving a signal detection value set to TRUE again.